1. Field of the Invention
The invention relates to a light source module, and particularly relates to a back light module and a display device using the back light module.
2. Description of Related Art
As the electronic products are more and more commonly used in recent years, display devices (e.g. liquid crystal display (LCD)), which plays an important role in the electronic products, have become the focus of the designers. A display device includes a display panel and a back light module. Some display panels do not have the light-emitting function, so the back light module is provided at the bottom of this kind of display panels as the light source for the display function.
Meanwhile, the display devices nowadays tend to be designed with a slim border. To meet the requirement of having a slim border, not only the non-display region for configuring the wiring at the periphery in a display panel is required to be slim, the design of the back light module also needs to be adjusted. The light guide plate (LGP) and light source used by the back light module are configured together in an assembling frame. In addition, a supporting pin or supporting block is usually arranged between the light guide plate and the assembling frame, so as to provide support and position the light guide plate in the frame. Therefore, the shape of the periphery of the light guide plate needs to correspond to the supporting structure aforementioned. For example, a recess part arranged at the periphery of the light guide plate needs to match the supporting structure, so as to provide the function above. However, when the back light module using the light guide plate emits light, light-jetting effect commonly occurs around the periphery of the recess part of the light guide plate of the back light module. Namely, the light emitted by the back light module through the light guide plate is easily interfered by the recess part. Therefore, the light is not evenly emitted at the recess part. As a result, the back light module does not provide a preferable light-emitting effect, and the display device using the back light module tends to have the defect of mura, which influences the display effect of the display device.